The Prime Minister guessed that a "value sliced white loaf" would cost "well north of a pound" when he was quizzed about the cost of living on LBC 97.3 Radio.
When presenter Nick Ferrari told him it actually cost around 47p, Mr Cameron revealed that he prefers to use an electric breadmaker.
Mr Cameron added, "I don't buy the ... look I'm trying to get my children to eat the sort of granary - and they take it actually, they like my home-made bread."
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